1. Field of the Invention
The present invention relates to image forming apparatus and particularly to image forming apparatus capable of communication with external devices.
2. Description of the Related Art
Image forming apparatus such as copying machines employing the electrophotographic process, facsimiles and optical printers are widely used as means for forming hard copy images. Such image forming apparatus usually include CPUs (Central Processing Unit) including microprocessors and so forth, in which each portion is controlled according to a control program.
Now, conventionally, as described in Japanese Patent Laying-Open No. 59-142559, for example, a control system in which each copying machine and a control unit (host) are connected to each other through a communication line in order to concentrically control a plurality of copying machines has been known.
Copying machines configuring such a control system include means for storing data corresponding to control items and transmit the data to the host according to a command from the host.
Conventional control items were mainly for grasping operational (use) conditions of copying machines, such as the number of copies for each user and sizes of employed paper.
That is, conventional control systems are configured with an object of enabling easy totalization of data for implementing rational use of each copying machine at users having a plurality of copying machines such as official agencies and companies, that is, payment by beneficiaries of maintenance cost and equalization of used amount among users.
Recently, in order to implement high efficiency in maintenance for image forming apparatus, a maintenance control system is in progress in which a host provided at a service station where servicemen are waiting and each of a plurality of image forming apparatus provided at each user are connected in an on-line manner.
In the present specification, maintenance means whole activity for keeping operational conditions (hereinafter, referred to as "condition") of an image forming apparatus normal, including work (field work) by a serviceman at a user such as periodic checking and repair of troubles (fails and bad conditions) and activities for supporting the field work, that is, totalization and analysis of conditions of trouble occurrence and improvements in the working manual.
In a maintenance control system, controlled items are mainly related to conditions of image forming apparatus, and image forming apparatus have a function of transmitting condition data corresponding to conditions indicated by an output signal of a sensor in each portion to a host.
By controlling conditions of each image forming apparatus at the service station, if a trouble occurs, a serviceman can estimate contents of the trouble with the condition data and make a visit to a user with prepared necessary repairing parts.
On the other hand, conventionally, a serviceman manually writes contents of his work in a maintenance control sheet at the end of the field work. The written items expressing contents of the work include a name of the serviceman, work time, names of replaced parts if any, portions to which adjustment or cleaning is applied.
The maintenance control sheet, in addition to be used as a bill for a demand for the work charge, is kept at the service station to be utilized for record of measures taken according to conditions of an image forming apparatus, that is, history information of maintenance for the image forming apparatus. For example, in the next field work, the work time can be reduced by confirming parts recently replaced referring to the maintenance control sheet to omit adjustment and checking for the parts.
Conventionally, however, recording in the maintenance control sheet took a large amount of time and labor, so that there has been a problem of a great burden for the serviceman. Especially, if more detailed records of work contents are required, for example, information of how adjustment was made together with where the adjustment was made, a burden of the serviceman further increases. Accordingly, actually, the written items can not be increased so much. Therefore, it is difficult to obtain more detailed history information.
Also, when the information written in the maintenance control sheet is managed by the host at the service station, there has been a problem that it was difficult to obtain history information with high reliability because input mistakes might be made in the input process for inputting the information from the maintenance control sheet to the host.
Generally, in order to enhance work efficiency in the field work in maintenance, more information related to events of the field work, or so-called field information (market information) is preferably utilized. That is to say, if information indicating measures taken by a large number of servicemen are collected to accumulate guide information instructing effective measures for various kinds of conditions (information indicating work procedure), a serviceman can reduce his work time by utilizing the guide information.
As described above, however, the maintenance control system controlling only conditions of each image forming apparatus had a problem that the field work by the serviceman can not be made efficient by utilizing the field information.